Tourist visa for rio carnival

Check your BR consulate's site for the information. You do not need an invitation for a tourist visa. Just submit application and all information
http://lagos.itamaraty.gov.br/en-us/
May take awhile

Thanks Tex, checked that already, I appreciate.
I need to know if accomodation is enough or i do really need an invite too

Here's the list of what the Brazilian Consulate General in Lagos will require in order to issue you a VIVIS visa for tourism:

http://lagos.itamaraty.gov.br/en-us/visitor_(for_tourism,_business_and_other_situations).xml

I'm not sure what you mean by "all ticket companies do not provide tickets till I get to Rio"; the Consulate General will require you to have a documented hotel reservation and a round trip air ticket,  both of which you should be able to get in Nigeria.

If you don't have friends or family who live legally in Brazil, you won't be able to get an invitation letter.  Contact the Consulate at the email address indicated on the page above to find out if you can obtain a visa without one.

Carnaval 2020 is Tuesday, February 25.  Visa processing time is 21 working days, so there's no time to lose.

Thanks abthree for the prompt response
I already paid for the tickets to attend the carnival.
I'll send an email to the consulate as suggested.
Thanks

Good luck -- I  hope it works out for you.

Brazil's biggest concern is people overstaying their visas.  If your information, especially your employment and financial information, convince the Consulate that you plan to come home after your trip, that should help you get approved.

Thank abthree.
I will continue to update the progress here

As said you will need lodging reservations or an address or a BR citizen is staying with someone, return air ticket for the visa and PF entry into BR.
I too have not heard of any airline or a company not issuing a ticket to be printed. You will need all just to check-in to fly.
Additionally once you have such, PF will ask you for all that info and sufficient funds for the trip upon arrival.